This invention relates to the field of absorbent articles in general, and more particularly to absorbent articles that provide leakage protection and/or skin protection, as well as methods for using and preparing same, and novel compositions and composites for use in same.
Disposable absorbent articles typically include a moisture-impervious backing sheet, an absorbent pad, and a liner sheet that contacts the body of a person wearing the article. In addition, elasticized regions are provided around the edges of the article to secure the article about the waist and legs of a wearer. Diapers typically further comprise opposed front and rear waist portions defining a waist opening, a crotch portion disposed there between, and a pair of elastically contractible leg openings along the side edges of the crotch portion. Disposable diapers having elasticized margins for placement about the legs of a wearer are disclosed in U.S. Pat. Nos. 4,050,462 and 5,092,861. An absorbent article having elasticized side margins and waist band margins are shown in U.S. Pat. No. 4,300,562.
Despite previous advancements in the field of absorbent articles, persons of ordinary skill in the art continue their efforts to produce more comfortable garments which are better able to contain urinary and fecal excretions. For instance, problems with prior diaper designs include leakage of urinary or fecal material from the garment. Prolonged contact of liquid or semi-solid excreta with the skin of the wearer is also a continuing problem in the art. For example, the moisture vapor and heat generated by the bodily exuded trapped within a diaper may lead conditions adjacent to wearer""s skin which promotes skin irritation, infection, and the like. Although a plastic backsheet, as described above, is generally effective in precluding the passage of bodily exude outwardly, the backsheet is not efficient in preventing lateral leakage of liquids from the opposed side portions of the core sideward between the leg gathers of the backsheet and the wearer""s skin. One solution to this problem, the tightening of leg gathers, presents problems in terms of the comfort of the baby and further skin irritation. Various other approaches had been attempted to address the lateral leakage of liquids from absorbent articles.
For example, U.S. Pat. No. 6,114,596 to Nayak et al. discloses a breathable diaper, feminine hygiene, or like disposable sanitary product having a cloth-like outer surface and including a plurality of materials from the skin-facing side outwardly, a topsheet, a core, an optional barrier, and a backsheet. The disclosed topsheet is formed of liquid- and vapor-permeable hydrophilic material, and the core is formed of highly absorbent material disposed outwardly of the topsheet for absorbing liquid received through the topsheet. The disclosed core has an inter surface in liquid communication with the topsheet and an outer surface. The disclosed optional barrier is formed for a multi-layer non-woven material which is hydrophobic and vapor-prominentable for limiting the outward escape of liquid therethrough while enabling the outward escape of heat and water vapor therethrough. The disclosed barrier has a base disposed adjacent the core outer surface. The disclosed backsheet is formed of a multi-layer non-woven material which is hydrophobic and vapor permeable for limiting the outward escape of liquid therethrough while enabling the outward escape of heat and water vapor therethrough. This backsheet is disclosed as being disposed at least partially as an outer surface of the diaper.
U.S. Pat. No. 6,017,336 to Sauer discloses an absorbent article which includes a pair of compression resistant containment barriers which are configured to inhibit the lateral flow of fecal exudates along the surface of the absorbent article. The containment barriers are disclosed as being laterally spaced apart to provide a void space between the wearer""s back side and the surface of the absorbent article for containing body exudates. Each containment barrier is disclosed as defining a width to height ratio of at least about 0.5 and a compression resistance of at least about 50%. The absorbent article is disclosed as optionally including a containment dam which is located on the body facing surface of the absorbent article and which is configured to inhibit a longitudinal flow of fecal exudates along the surface of the absorbent article.
U.S. Pat. No. 5,597,906 to Roe, et al. discloses an absorbent article comprising a liquid pervious topsheet, a liquid pervious backsheet joined to at least a portion of the topsheet, an absorbent cord disposed between at least a portion of the topsheet and the backsheet, and a waste management element disposed in at least a portion of the crotch region. The waste management element preferably has an acceptance under pressure value of greater than about 0.50 grams of a viscous fluid bodily waste per square inch of the waste management element millijoule of energy input. The waste management element is also disclosed as having a storage under pressure values of at least about 0.70 grams of the viscous fluid bodily waste per square inch of the waste management element. The waste management element is also disclosed as optional having an Immobilization Under Compressed Inversion valve of greater than about 70% of the viscous fluid bodily waste accepted by the waste management element. The waste management is disclosed as being located anywhere in the article, including the crotch region.
U.S. Pat. No. 5,941,864 to Roe discloses a disposable absorbent article, such as a diaper having a first topsheet with apertures large enough for low-viscosity fecal material to pass through to a fecal material storage element. The fecal material storage element is disclosed as immobilizing the fecal material in position for dewatering, so that the liquid components of the fecal material are absorbed by the core and solid components of the fecal material are separated from the liquid components, to provide for easier-cleaning of the wearer when the soiled disposable absorbent article is removed.
U.S. Pat. No. 5,941,862 to Haynes et al. discloses absorbent structures comprising a first layer, a second layer juxtaposed in facing relation with said first layer, wherein at least one of the layers is fluid pervious. These structures are disclosed as having a continuous region between said first and second layers comprising hydrogel-forming polymer that is substantially uniformly distributed throughout the region. The continuous region is disclosed as at least partially surrounding multiple, spaced apart zones between said layers, which zones are substantially devoid of hydrogel-forming absorbent polymer. The first and second layers are disclosed as being bonded together such that said hydrogel-forming absorbent polymer is substantially immobilized when in dry state, an preferably at sites within plurality of the zones.
U.S. Pat. No. 5,558,655 to Jezzi et al. discloses in absorbent article, such as diaper, which comprises a composite structure of a xe2x80x9ctwo-dimensionalxe2x80x9d or very flat, apertured film or nonwoven layer, in combination with a. fluid transferring layer and a superabsorbent polymer-containing laminate, and a absorbent core below the laminate to achieve superior dryness. The superabsorbent poylmer-containing laminate is disclosed as containing airlaid fibrous components and superabsorbent polymers and as swelling to at least three times its dry caliper upon fluid introduction in order to achieve movement of the coverstock away from the absorbent core which permits the coverstock to remain relatively dry and avoids rewetting.
U.S. Pat. No. 6,040,251 to Caldwell discloses barrier webs at a certain desirable physical qualities such as water resistance, increased durability, improved barrier qualities and the like. Barrier webs are disclosed as comprising a web that has been treated with a curable shear thinned thixotropic polymer composition which is adapted to be substantially impermeable to liquids, permeable to gases and impermeable to microorganisms. Further, the barrier webs are disclosed as being either impermeable to all microorganisms or impermeable to microorganisms of certain sizes. Also disclosed are fabrics that are capable of either selectively binding certain microorganisms, particles, or molecules depending upon what binding partners are incorporated into the polymer before application to the fabric.
U.S. Pat. No. 5,945,175 to Yahiaoui et al discloses a coated porous substrate composed of a hydrophobic polymer which is substantially uniformly coated with a hydrophilic polymeric material. The substrate may be a sheet-like material, examples of which are forms, fibers, and fibrous webs. The fibrous webs are disclosed as desirably being nonwoven webs. The coating on the substrate is disclosed as being durable to an aqueous medium at a temperature in a range of from about 10xc2x0 C. to about 50xc2x0 C. and does not significantly suppress the surface tension of an aqueous medium-with which the coated substrate may come in contract. The hydrophobic polymer is disclosed as being a polyolefin, such as polyethylene or polypropylene. The hydrophilic polymeric material is disclosed as being a polysaccharide or a modified polysaccharide.
U.S. Pat. No. 6,117,121 to Faulks et al. discloses an absorbent article including an absorbent core located between a bodyside liner and an outer cover. The absorbent article is disclosed as having a leg cuff mounted to a base structure in the crotch portion thereof. The leg cuffs are disclosed as being partially stretched when attached to respective longitudinal side portions near the crotch portion of the absorbent article.
U.S. Pat. No. 6,107,539 to Palumbo et al. discloses disposable absorbent articles comprising a backsheet, a topsheet, a fluid acquisition/distribution region and at least one fluid storage region, said article having a total product acquisition performance of more than 3.75 ml/sec in the first gush and more than 0.5 ml/sec in the fourth gush and an in bag stack height of less than 9.9 mm, characterized in that said topsheet allows it to retain no more then 0.25 g of fluid as measured by the topsheet-on-acquisition-material-wetness test, and that said acquisition/distribution region has a drip capacity of at least 5.0 grams of fluid per gram of material.
U.S. Pat. No. 5,935,118 to Gryskiewicz et al. discloses an absorbent article that includes a garment shell and at least one liquid containment beam formed of an absorbent material. The liquid containment beam has an attachment edge bonded to the garment shell so that the containment beam can lie against the garment shell and also pivot about an axis defined by the attachment edge. For comfort during use, the containment beam desirably has a width to thickness ratio of at least about 3:1. In particular embodiments, the absorbent article includes pairs of inner and outer containment beams, with the inner containment beams adapted to lie against the garment shell and the outer containment beams adapted to lie against the inner containment beams.
U.S. Pat. No. 6,087,550 to Anderson-Fischer et al. relates to water responsive thermoplastic compositions and articles constructed thereof. This invention particularly relates to thermoplastic copolyester compositions useful for the manufacture of disposable articles such as disposable diapers and feminine napkins. More particularly, this invention relates to thermoplastic copolyester compositions that are useful as a raw material in the manufacture of nonwovens, barrier films or coatings, as well as for various improved hot melt adhesive compositions useful for incorporating hydrophilic features into disposable articles.
U.S. Pat. No. 6,120,783 to Roe et al. discloses web materials which have two or more skin care compositions disposed thereon. The skin care compositions are transferable to the wearer""s skin by normal contact and/or wearer motion and/or body heat. The skin care compositions disclosed in the present invention are selected to maintain and/or improve the skin health of the wearer upon transfer during use, for example, to provide a skin protective barrier or a therapeutic benefit; to minimize the abrasion between the cuffs and skin in the area where the cuffs contact the wearer""s skin, resulting in less skin irritation; to improve BM clean up on the skin, or to improve the barrier properties of the cuffs. Web materials of the present invention have a wide range of potential uses in both durable and disposable articles, but are particularly well suited for use in disposable absorbent articles such as disposable diapers, incontinent briefs, training pants, sanitary napkins, and the like.
U.S. Pat. No. 5,683,809 to Freeman et al. discloses protective articles such as diapers, having filmless hydrophobic barrier elements such as cuffs and backing sheets. The barrier cuffsxe2x80x94which can be, for instance, leg cuffs and waistbandsxe2x80x94and the backing sheets can be provided from fabrics having a fabric weight of at least 10 gsy.
U.S. Pat. No. 5,928,209 to Bodford et al. discloses a breathable diaper, feminine hygiene, or like disposable sanitary product construction includes a plurality of materials including, from the skin-facing side outwardly, a topsheet of liquid- and vapor-permeable hydrophilic material. A core of highly absorbent material is disposed outwardly of the topsheet for absorbing fluid received through the topsheet, the core having an inner surface in fluid communication with the topsheet. A backsheet is disposed at least partially as an outer surface of the construction and is formed of a pouch defined by two layers of a non-woven hydrophobic and vapor-permeable material, with absorbent or superabsorbent particles therebetween, so that the backsheet limits the outward escape of liquid therethrough while enabling the outward escape of heat and water vapor therethrough. Each backsheet layer is an at least two-layer spunbound-meltblown SM or an at least three-layer spunbond-meltblown-spunbond SMS.
U.S. Pat. No. 5,990,377 to Chen et al. discloses a dual-zoned, three-dimensional, resilient absorbent web is disclosed which is suitable as body-side liner for absorbent articles such as feminine pads, diapers and the like. When used as a liner in absorbent articles, the dual-zoned web combines the advantages of apertured films and soft, nonwoven cover layers in one structure while still being inherently hydrophilic. The liner comprises a web of wet-resilient, hydrophilic basesheet having a three-dimensional topography comprising elevated regions onto which hydrophobic matter is deposited or printed and a plurality of spaced apart depressed regions. In a preferred embodiment, the hydrophobic matter applied to the elevated regions of the basesheet comprises hydrophobic fibers in a contiguous nonwoven web which has been apertured or provided with slits or other openings, such that the apertures or openings overlay a portion of the depressed regions. The elevated hydrophobic regions enhance dry feel and promote fluid flow toward the lower hydrophilic regions, which comprise the exposed depressed regions of the basesheet. The basesheet is preferably in liquid communication with underlying absorbent material, most preferably a stabilized airlaid cellulosic material or compressed stabilized fluff such that the absorbent material can wick fluid out of the basesheet by capillary action. When soft, hydrophobic fibers are deposited on the elevated regions, the liner also has a soft, cloth-like feel in addition to a dry feel in use.
U.S. Pat. No. 6,120,488 to VanRijswijck et al. discloses an absorbent article, such as a diaper, containing cuffs and a topsheet with one or more skin care compositions disposed thereon. The skin care compositions are transferable to the wearer""s skin by normal contact and/or wearer motion and/or body heat. The skin care compositions disclosed in-the present invention are selected to maintain and/or improve the skin health of the wearer upon transfer during use, for example, to provide a skin protective barrier or a therapeutic benefit; to minimize the abrasion between the cuffs and skin in the area where the cuffs contact the wearer""s skin, resulting in less skin irritation; to improve BM clean up on the skin, or to improve the barrier properties of the cuffs.
U.S. Pat. No. 5,817,079 to Bergquist et al. discloses in absorbent products, such as sanitary napkins, discreet areas of dry fibrous materials such as fluidrepellent materials are precisely placed in various planes within the product so as to provide barriers to bodily fluid leakage from the product. In a preferred embodiment, hydrophobic fibers are placed around the periphery of a central absorbent area of an absorbent product to discourage and/or prevent side or end leakage from the product.
U.S. Pat. No. 5,830,201 to George et al. discloses a flushable diaper for use on the body of an infant or adult. An envelope has inner and outer walls which are secured together at their outer periphery to form an inner cavity. The outer wall is comprised of a hydrophobic outer layer together with a hydrophilic inner layer. The inner wall is comprised of a hydrophobic outer layer together with a hydrophilic inner layer. The inner and outer walls are separated by an interior cavity which contains one or more containers. The container is comprised of either a single layer or a laminated wall which forms a chamber that encloses a charge of water. The laminated wall is comprised a hydrophobic inner laminate and a hydrophilic outer laminate. When manually ruptured, the containers release water into the double walled envelope, which causes disintegration of the hydrophilic inner layers of the double walls, along with the hydrophobic outer layers. An absorbent member is carried on the inner wall of the envelope, and the absorbent member comprises a fluid pervious cover which encloses an inner body that is comprised of a material which is sufficiently hydrophilic to absorb urine and other fluids from the body while maintaining structural integrity of the inner body and to also absorb water in an effective amount to cause the inner body to disintegrate into small pieces.
U.S. Pat. No. 5,885,266 to Chihani et al. discloses an absorbent article such as a diaper, an incontinence guard or a sanitary napkin includes a liquid-permeable outer sheet, a liquid-impermeable bottom sheet and an absorbent body placed therebetween. The outer sheet and the absorbent body are at least partially joined together with a hydrophilic glue.
As is apparent from the foregoing, each of the prior references present a variety of means for controlling leakage in absorbent garments. However, all of these proposed means are deficient in terms of effectiveness and low product quality, mechanical complexity in design, and/or associated cost inefficiencies.
In view of the deficiencies of the various products and processes disclosed in the above discussed references, it is highly desirable to provide cost-efficient absorbent articles that display superior leak protection, as well as novel compositions and composites for use in said absorbent articles. Further, it is highly desirable to provide a cost-efficient process for producing absorbent articles having superior leak protection. Moreover, it is also highly desirable to provide cost-efficient absorbent articles, and methods for preparing such articles, that confer secondary benefits of skin wellness to the users of said articles, in addition to superior leak protection.
The present invention provides cost-efficient absorbent articles, and novel compositions and composites for use in same, that display unexpectedly superior leak protection. Further, the present invention provides a cost-efficient process for producing absorbent articles having superior leak protection. Moreover, the present invention provides cost-efficient absorbent articles, methods for preparing and using such articles, and novel compositions and composites for use in same, that confer secondary benefits of skin wellness to the users of said articles in addition to superior leak protection.
One embodiment of the present invention is an absorbent article comprising: a permeable topsheet; a substantially impermeable backsheet; an absorbent core disposed between said permeable topsheet and said substantially impermeable backsheet; and a hydrophobic composition selectively disposed between the skin-opposing surface of the substantially impermeable backsheet and the skin of a wearer of the absorbent article to contain leakage.
A further embodiment of the present invention is an absorbent article comprising: a permeable topsheet; a substantially impermeable backsheet; an absorbent core disposed between said permeable topsheet and said substantially impermeable backsheet; and a hydrophobic composition disposed between the skin-opposing surface of the substantially impermeable backsheet and the skin of a wearer of the absorbent article at a leak protection zone or plurality of leak protection zones; wherein said hydrophobic composition comprises a hydrophobic substance effective for skin protection, a substance effective for skin care, a substance effective for skin wellness, a substance effective for skin improvement, a substance perceived as having a skin wellness benefit or combinations thereof.
A still further embodiment of the present invention is an absorbent garment comprising: a front waist portion and a rear waist portion cooperating to form a waist opening; a crotch region formed between said front waist portion and said rear waist portion; a pair of leg openings on opposed sides of the crotch region; a permeable topsheet, a substantially impermeable backsheet and an absorbent core positioned between said topsheet and said backsheet; and a hydrophobic composition disposed on said permeable topsheet at a leak protection zone or plurality of leak protection zones.
An even further embodiment of the present invention is an absorbent article comprising: a permeable topsheet; a substantially impermeable backsheet; an absorbent core disposed between the permeable topsheet and the substantial impermeable backsheet; a tissue layer disposed between the absorbent core and the permeable topsheet; and a hydrophobic composition disposed on said tissue layer at a leak protection zone or plurality of leak protection zones.
Another embodiment of the present invention is a method for preparing an absorbent article comprising: identifying a leak protection zone or a plurality of leak protection zones; disposing a hydrophobic composition at one or more predetermined areas on a substrate; and forming an absorbent article comprising the substrate such that the one or more predetermined areas correspond to the leak protection zone or plurality of leak protection zones.
Yet another embodiment of the present invention is a method for preparing an absorbent article comprising: disposing a hydrophobic composition at predetermined areas on a tissue layer or a permeable topsheet; and forming said tissue layer or permeable topsheet into an absorbent core such that the predetermined areas correspond to a leak protection zone or a plurality of leak protection zones.
Still another embodiment of the present invention is a composition in an absorbent article for providing leak protection and/or skin wellness comprising: an effective amount of a hydrophobic substance selected from the group consisting of cocoa butter, petrolatum, dimethicone, a zinc oxide preparation, beeswax, lanolin, jojoba oil and combinations thereof effective in providing leak protection when selectively disposed at a leak protection zone or plurality of leak protection zones on said absorbent article.